For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningInstallation Procedure
Drill 8 mm (5/16 in) for plug welding along the edges of the front
compartment upper side rail as noted from the original panel.
Clean and prepare the attaching surfaces for welding.
Position the front compartment upper side rail on the vehicle.
Verify the fit of the fr ...
Radio Reception
Frequency interference and static can occur during normal radio reception if
items such as phone chargers, vehicle convenience accessories, and external electronic
devices are plugged into the accessory power outlet. If there is interference or
static, unplug the item from the accessory power ...
Installation Procedure
Drill 8 mm (5/16 in) for plug welding along the edges of the service
panel as noted from the original
panel.
Clean and prepare the attaching surfaces for welding.
Position the body lock pillar inner panel on the vehicle.
Verify the fit of the panel.
Clamp th ...